Use the numbers 2, 3, 4 and 5 and the symbols + and = to make a true equation. Conditions: Each must be used exactly once and no other numbers or symbols can be used.

A number can be multiplied by multiple of nine
i.e 9 18 27 36 45 ...

and the resulting number consist of only one digit.

Can you identify the number ?

Place a mathematical symbol between the numerals 5 and 9 in such a way that the resulting number is greater than 5 but smaller than 9.

Can you find a seven digit number which describes itself. The first digit is the number of zeros in the number. The second digit is the number of ones in the number, etc. For example, in the number 21200, there are 2 zeros, 1 one, 2 twos, 0 threes and 0 fours.

Look at this sequence from top to bottom. What is the next number in the sequence?
1
11
21
1211
111221
312211

Baseball bat and ball cost $100. If the bat cost $99 more than the ball, what is the cost of each?

John replied, when asked how old he was. In 2 years he will be twice as old as he was five years ago.' How old is he ?

Double it and multiply it by 4. Then divide it by 8 and you’ll have it once more. What number is it?

What does this mathematical rebus means ?

If one and a half boys, eat one and a half burgers in one and a half hours.

How many burgers can 9 boys eat in 3 hours?